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研究了碳酸铝铵的合成，并对碳酸铝该加热过程中的物相变化和。α－Al2O3籽晶对θ－Al2O3→α－Al2O3的相变的影响进行了分析．结果表明，将硫酸铝铵溶液以小于20mL／min的速度滴入碳酸氢按溶液，可以合成颗粒尺寸小于5um的碳酸铝铵沉淀．不合籽晶的碳酸铝铵煅烧时θ－Al2O3→α－Al2O3相变温度为1100℃，获得的α－Al2O3粒径约为70um；质量分数为5％的α-Al2O3籽晶可将该相变温度降至900℃，获得的α-Al2O3粒径约为30nm．烧结实验表明，经1400℃，2h烧结后，粒径约30um的α-Al2O3粉可达到98．5％理论密度；而粒径约70um的α－Al2O3粉在相同烧结条件下的相对密度为95.0％.
The synthesis of aluminum ammonium carbonate was studied, and the phase transformation and the transformation of aluminum carbonate during the heating process were investigated. The influence of α-Al2O3 seed on the phase transformation of θ-Al2O3 → α-Al2O3 was analyzed. The results show that the ammonium aluminum sulfate solution is less than 20mL / min speed of dropping bicarbonate solution, can be synthesized particle size less than 5um aluminum ammonium carbonate precipitation. When the amorphous aluminum ammonium carbonate was calcined, the phase transformation temperature of θ-Al2O3 → α-Al2O3 was 1100 ℃, and the particle size of α-Al2O3 was about 70um. The α-Al2O3 seed with mass fraction of 5% The temperature was lowered to 900 ° C and the α-Al2O3 particle size obtained was about 30 nm. Sintering experiments show that after calcined at 1400 ℃ for 2h, the α-Al2O3 powder with a particle size of about 30um achieves a theoretical density of 98.5%. The relative density of α-Al2O3 powder with a particle size of about 70um under the same sintering conditions is 95.0 %.